From 71748d469dfa312a3e263adb6611b3e52ec3fc01 Mon Sep 17 00:00:00 2001
From: Tom Gustafsson <tom.gustafsson@iki.fi>
Date: Fri, 12 Apr 2024 15:26:34 +0300
Subject: [PATCH] add p2e

---
 skfem/mesh/mesh.py | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/skfem/mesh/mesh.py b/skfem/mesh/mesh.py
index 9df63d8b..97d891ec 100644
--- a/skfem/mesh/mesh.py
+++ b/skfem/mesh/mesh.py
@@ -160,7 +160,7 @@ def p2f(self):
 
     @property
     def p2t(self):
-        """Return incidence matrix between elements and vertices."""
+        """Incidence matrix between elements and vertices."""
         from scipy.sparse import coo_matrix
         t = self.t.flatten('C')
         return coo_matrix(
@@ -171,6 +171,13 @@ def p2t(self):
             dtype=np.int32,
         ).tocsc()
 
+    @property
+    def p2e(self):
+        """Incidence matrix between edges and vertices."""
+        p2t = self.p2t
+        edges = self.edges
+        return p2t[:, edges[0]].multiply(p2t[:, edges[1]])
+
     def dim(self):
         return self.elem.refdom.dim()